Repeat Problem 16.18 using the generalized charts, instead of ideal gas behavior.
\begin{aligned}& \left( Z _1- Z _2\right)=5000 \,m , \quad P _1=15 \,MPa \\& T =40^{\circ} C = const \\& T _{ r }=\frac{313.2}{304.1}=1.03, \quad P _{ r 1}=\frac{15}{7.38}=2.033 \\& \text { Equilibrium: } \quad- w _{ REV }=0=\Delta g +\Delta PE\end{aligned}
g _2- g _1= h _2- h _1- T \left( s _2- s _1\right)= g \left( Z _1- Z _2\right)=\frac{9.807 \times 5000}{1000}=49.04 \,kJ / kg
From Figures D.2 and D.3,
Trial and error. Assume P _2=55 MPa \quad\left( P _{ r 2}=55 / 7.38=7.45\right)
Too low so assume P _2=60 \,MPa \quad\left( P _{ r 2}=60 / 7.38=8.13\right)